Container loading and unloading

ABSTRACT

A container loading and unloading method in which a buffer is provided between a container crane and a rear conveyance facility on a container crane so that some of the containers may be deposited upon said buffer when the containers are transferred from the container crane to the container carriage or vice versa.

United States. Patent 1 1 Watatani May 28, 1974 [54] CONTAINER LOADING AND UNLOADING 1,305,802 6/1919 Hulett 214 14 1,476,557 12/1923 Travell 212/15 [75] t Tokyo Japan 2,701,005 2 1955 Bertel v. 212 11 x 73 Assignee; l hik w ji fl i jukogyo 3,630,390 12/1971 Tax 214/14 h ki K ish Tokyo, Japan FOREIGN PATENTS OR APPLlCATlONS {22] Filed: Oct, 28, 1971 578,884 7/1959 Canada 214/14 467,748 1019211 G .2121] 21 Appl. No.: 193,276 I "many I Primary Examiner-Albert J. Makay [30] F i A li i p i i D Attorney, Agent, or Firm-Scrivener, Parker, Scriv- Dec. 30, 1970 Japan 45422322 and Clarke 52 us. 01 214/87, 212/11, 212/18, 1571' ABSTRACT 214/14 A container loading and unloading method in which a [51] Int. Cl B63b 27/00 buffer is provided between a container crane and a [58] Field of Search 214/14, 87; rear conveyance facility on a container crane so that 212/ 14-16, 22, 10,11, 18 some of the containers may be deposited upon said buffer when the containers are transferred from the [56] References Cited 2 container crane to the container carriage or vice UNITED STATES PATENTS Versa- 1,152,879 9/1915 Colby et a1. 212/15 1 Claim, 6 Drawing Figures PATENTEU MAY 2 8 i974 SHEET]. 0? 4 INVENTOR MINORU WATA TAN l y W Aaw manzomz m 3.812.987

. INVENTOR M l NORU WATATANI ATTORNEYS memmm m4 7 38121987 INVENTOR MINORU WATATANl ATTORNEYS CONTAINER LOADING AND UNLOADlNG The present invention relates togenerally a container crane and more particularly a container ship loading and unloading system. The primary object of the present invention is to improve the efficienty of a container crane operation, to make full use of a limited container loading and unloading space and to facilitate the smooth operation of the land vehicles by providing a storage or storages within a container crane or between a container crane and a container transfer machinery so as to store therein temporarily the containers to be loaded and unloaded, the hatch covers, andthe like.

The trailers or the like are generally used to transport the containers to and from the container cranes so that is is extremely difficult to attain the exact container transfer timing between the container crane and the trailers. The reason is that there exists a difference between the time required for a trailer to transport an import container unloaded by the container crane from a container ship to a container yard and then to return to the container crane and the time required'for the container crane to unload an import container from the container ship. Therefore the container crane is idled when the trailers do not come back from the container yard. ln other words, the container crane must be operated depending upon the traveling schedules of the container trailers. In order to overcome this problem a large number of container trailers have been used so as to minimize the idling time of the container crane and to reduce the mooring time of the container ship.

The recent trend is toward the automatic container conveyance between the container yard and the container vessel. For this purpose, the carriages running on the rails or conveyors are used, but it is still difficult to attain the perfect synchronization between the operations of the container cranes and the carriages or conveyors.

The term synchronization" used here means that a time required for a conveyor or carriage for example for transporting an unloaded import container from a crane to a specified location in a container yard and returning back to the crane, coincides with a time required for the crane to unload the next import container. In other words, the synchronization means that the service time of a carriage or conveyor is equal to that of the container crane. In order to attain the synchronization or timing, an operator of the container crane must calculate a time of one cyclic operation of a carriage or the like for transporting an import container to a specified location in a container yard, unloading it and returning back to the container crane. And the operator must unload the next container just in time when the carriage returns to the container crane. It is seen that a container-unloading time varies for each container so that the adjustment of the container-unloading timing is very troublesome for the operator and that it is almost impossible in practice to attain such perfect synchronization or timing. Therefore, according to the present invention, a number of carriages used is increased and used as a buffer to mini mize the idle time of the container crane and the turnaround time in port of the ship.

It is of course desired that the rate of operation of the container crane is increased while the container loading and unloading cycle is reduced so that the conductor loading and unloading time may be minimized.

According to the present invention the containers, hatch covers and the like may be temporarily stored in a storage provided on the container crane so that the operationof the container crane may be carried out in dependently of the operation of the container trailers of the like. The containers, the hatch covers and the like which are transported to the container trailers or the like are transferred onto the container trailers or the like by the auxiliary container loading and unloading machinery. The containers, the hatch covers and the like which are not required to be transported to the container yard or the like may be temporarily stored on the storage. Therefore the efficiency of the container crane operation may be much improved and the container yard or the like may be fully utilized. More particularly according to the present invention the containers, hatch covers and the like which must be unloaded from the container ship and transported to the container yard are hoisted or lifted by the container crane and unloaded on the storage. The container hatch covers and the like on the storage are transferred onto the container trailers or the like by the auxiliary loading and unloading machinery. In general the container ship does not have a sufficient space for storing therein the containers, hatch covers and the like which are not required to be unloaded from the container ship so that they will not adversely affect the smooth container unloading and loading operation. If they are stored temporarily on the wharf below the container crane-they become the obstacles to the smooth operations of the container trailers or the like. However, according to the present invention they may be stored in the storage on the-container crane so that the smooth operations of the container trailers or the like will not be adversely affected at all. After the completion of the container loading and unloading operation, they may be lifted again and stowed into the container ship.

According to the present invention the storage is provided within the container crane between the container crane and the container trailers or the like so that some of the containers, hatch covers and the like may be temporarily stored until they are transferred from the container crane to the land vehicles such as container trailers or from the land vehicles to the container crane.' Therefore the efficiency of the container crane operation as well as land vehicle operation may be considerably increased, and the mooring time of the container ship may be remarkably reduced. Furthermore the containers, hatch covers and the like which are not required to be transported to the container yard or the like may be temporarily stored in the storage during the container loading and.unloading operation and then may be stowed again into the container ship after the container loading and unloading operation. The novel features of the container crane in accordance with the present invention may be summarized as follows: A storage is provided on the container crane erected on the container wharf or between the container crane and the land vehicles so that the containers, hatch covers and the like may be temporarily stored therein. The auxiliary container loading and unloading machinery is provided between the storage and the land vehicles so that the transfer of containers between the storage and the land vehicles may be accomplished.

Furthermore, the hatch covers whose storage has been difficult in the prior art may be stored on the stor- The rate of operation of the container crane on the container pier is influenced by the operation of the container carriages which transfer the containers between the container yard and the container crane. Therefore in order that the operations of the container crane and the container carriages may be independent from each other, there are provided a buffer shelf upon which are placed the containers for transit and an auxiliary loading and unloading machine for transferring the containers between the buffer and the container carriages. Thus the operation of the container crane is reduced to the transfer of the containers between the buffer shelf or beam and the container vesseland is independent from the operations of the container carriages, so that the rate of operation may be much enhanced. The buffer may be so arranged that the buffer storage may be displaced forwardly or backwardly of the container crane by the carriages or conveyors so that the hoisting and travel distances of the container crane may be minimized. Therefore the rate of operation may be further increased.

The present invention will become more apparent from the following description of some preferred embodiments thereof taken in conjunction with the accompanying drawings. In every system to be described hereinafter. the operation of a container crane is carried out prior to that of an auxiliary loading machine.

FIG. 1 is a schematic view illustrating a first embodiment of a container loading and unloading system in accord with the present invention;

FIG. 2a is a schematic view illustrating a variation of the container loading and unloading system shown in FIG. I;

FIG. 2b is a schematic top view looking in the direction indicated by the arrows AA in FIG. 2a;

FIG. 3a is a schematic view illustrating still another variation of the container loading and unloading system shown in FIG. I;

FIG. 3b is a schematic top view looking in the direction indicated by the arrows 8-8 in FIG. 3a; and

FIG. 4 is a schematic view illustrating still another variation of the container loading and unloading system shown in FIG. 3a.

Referring to FIG. I, a trolley track beam 1 is supported by and extended from one leg of a container crane below a girder A thereof along which trolley 8 for a container-crane travels transversely. A trolley 2 rides on the rails on the trolley beam 1, and a container 3 is lifted by a spreader 4 whose span may be adjusted depending upon the dimensions of the container 3. The container 3 which is lifted by, the spreader 4 is moved onto a shelf 5 supported by the legs of the container crane below the trolley track beam 1.

The spreader 4 is provided with a guide mast 6 for automatic operation.

Reference numeral 10, FIG. also, denotes a location where the hatch covers or container fixtures are temporarily stored.

The containers, hatch covers and the like may be temporarily stored on the shelf or upon the extension of the trolley track beam 1. When the auxiliary container loading and unloading machinery is not operated, they may be stored directly on the trolley track beam 1. When the auxiliary loading and unloading machinery is operated, the containers, hatch cover and the like cannot be stored temporarily upon the beam 1 so that the shelf 5 may be furtherextended for the temporary storage thereof. They may be also stored on the transverse beams, but it is preferable that they are stored on the shelf 5. l

The trolleys 2 and 8 are so operated that the spreader 4 and a spreader 7'of the container crane will not align vertically in operation. A rail 9, for the trolley 2 on the track trolley beam 1 is provided with a rack, and the trolleys are driven by synchronous motors. The travel of the trolleys on both sides is corrected as a number of racks is counted when the trolleys are driven. Reference numeral 9 denotes rails for the container crane. Operation for loading one container upon the shelf:

The container crane directly discharges an imported container upon a carriage and hoists an export container upon the shelf and stows it in a vessel in return stroke. The container to be exported is placed upon the shelf by the auxiliary loading machine. Operation for loading two containers:

The container unloaded from a container ship by the main container crane is placed upon the shelf, and an export container which has been lifted from a land vehicle and placed over the shelf adjacent to the import container by the auxiliary loading andunloading machinery is lifted and stowed in the container ship by the main container crane in its return stroke. When there is an import container on the shelf, the auxiliary loading and unloading machine lifts over the land vehicle.

The container loading and discharging system shown in FIG. 2a is a variation of the system shown in FIG. 1. The trolley track beam 1 is supported at a right angle relative to the direction of the travel of the container crane. The container 3 is hoisted by a pair of forks 11 whose spacing is adjustable depending upon the dimensions of the container and is placed upon the shelf 5. The hoisting and lowering of the container 3 are made by rods 10 which are directly attached to the trolleys 2 and are driven hydraulically. In FIG. 2a, two sets of auxiliary loading machines are provided symmetrically about the legof the container crane, but it is seen that one set of theauxiliary loading machine may be attached to a revolving machine attached to the leg of the container crane so that the auxiliary loading machine may rotate through in unison with each other.

In a container loading and unloading machinery shown inFIG. 3a instead of the shelf 5 shown in FIG. 1, storage beams 12 are extendedacross the whole length of the auxiliary loading and unloading machinery. A container upon the land vehicle is lifted upon the storage beams 12 byan auxiliary loading and unloading machinery as shown in FIG. 3b. A carriage 13 which automatically travels on the storage beams 12 serves as a buffer.

The span of the spreader 4 is adjustable depending upon the dimensions of the container 3 and is provided with the mast 6.

At least two carriages 13 are required. The height of the trolley track beam 1 of the auxiliary loading machine is such that the loading and unloading container may be passed through freely above the container 3 on the carriage 13.

The trolley track beam 1 for the auxiliary loading and unloading machinery is located lower than the girder along which the trolley for the main container crane travels, and is spaced apart from the storage beams 12 by a sufficient distance so that the containers on the carriages 13 may be freely moved along the storage beams below the trolley beam 1.

It is seen that instead of running the carriage upon the beams 12, a conveyor system may be provided.

OPERATION shown in H6. 4, the trolley beam 1 for the auxiliary loading and unloading machinery is provided below the girder along which the trolley for the main container loading and unloading machinerytravels. The first storage beams 12" are provided below the trolley track beam 1 so that the containers, hatch covers and the like may be stored upon the first storage beams 12''. The second storage beams 12' are interposed between the trolley track beams '1 and the first storage beams 12'.

The second storage beams 12' are shorter than the first storage beam 12" so that the containers on the first storage beams 12" may be lifted from both ends thereof upon the first storage beams 12' by the trolley 2 for the auxiliary loading and unloading machinery. Instead of the carriages which move along the first and second storage beams 12 and 12', the conveyors may be mounted upon them.

The container transported by the land vehicle is lifted and loaded upon the carriage upon the second storage beams 12 by the auxiliary loading and unloading machinery. Then the carriage is moved toward the right and stopped at the right end of the second storage beams 12'.v

When the auxiliary loading and unloading machinery is moving toward the land vehicle in order to lift the next export container, it lifts the import container upon the carriage at the left end of the first storage beams l2" and carries it over the land vehicle.

The export container upon the carriage at the right end of the second storage beams 12 is lifted and stowed into the container ship by the main container loading and unloading machinery. The import container unloaded from the container ship by the main container loading and unloading machinery is placed upon the carriage at the right end of the first storage beams 12''. Then the carriage moves over the first storage toward the left end thereof so that the import container is lifted and loaded upon the land vehicle and then the export container is lifted and loaded upon the carriage.

In FIG. 4 the carriages are shown as being moved along the first and second storage beams 12" and 12', but the conveyors may be mounted thereupon so that the handling of the import and export containers'between the main container loading and unloading machinery and the conveyors may be continuously effected.

When the time required for the carriages to travel from the loading and unloading positions at the left ends toward the right loading and unloading positions and then to return back to the left loading and unloading positions is longer than one loading and unloading cycle of the main container crane or the auxiliary loadingand unloading crane, there is some idling time for the latter, thus resulting in the low efficiency. Therefore the traveling time of the carriage must be equal to or shorter than one loading and unloading cycle.

In the container crane shown in H6. 4, th export containers may be stored on the first storage beams 12 whereas the import containers may be stored on the second storage beams 12'.

. The auxiliary loading machine, buffer and container crane may be assembled as an integral unit or may be individual units. For example, the container crane and the buffer may be assembled as a unit while the auxili ary loading machine may be provided as a separate unit. Alternatively, the buffer and the auxiliary loading machine may be assembled as a unit while the container crane may be provided as a separate unit.

it is preferable that thebuffer is provided at such a position where the traverse and hoisting motions of the container crane may be reduced or minimized. The buffer may be movable so that the motions of the loading machine which loads and discharges the containers from the rear container conveyance system may be minimized. That is, the buffer may be so arranged as to move toward the container .crane. Furthermore, the auxiliary loading machine may be movable so as to minimize the traverse displacement of the container crane.

According to' the present invention, the buffer is provided so that the container crane and thecarriages may be independent from each other. The container crane may handle the containers on the buffer so that the rate of operation of the container crane which is dependent upon the traveling conditions of the carriages may be increased. In addition, the automatic operation of the auxiliary loading machine is feasible.

Furthermore, the hatch covers whose storage has been difficult in the prior art may be stored on the storage so that the terminal station may be effectively used.

The present invention is very advantageous in increasingthe container loading and unloading efficiency at the container terminals when the invention is carried girder, a first storage beam being provided within the container crane structure below said trolley track beam for storing either loaded or unloaded containers handled by said auxiliary trolley loading and unloading device, carriages movably mounted on said trolley track beam adapted to receive the containers, and a second storage beam also within the container crane structure and being positioned between said trolley track beam and said first storage beam for storing either loaded or unloaded containers handled by said main trolley loading or unloading device.

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1. A container crane structure having a main girder along which a main trolley loading and unloading device travels transversely, a trolley track beam below the main girder upon which an auxiliary trolley loading and unloading device travels, said trolley track beam being transversely extended over a wharf below said main girder, a first storage beam being provided within the container crane structure below said trolley track beam for storing either loaded or unloaded containers handled by said auxiliary trolley loading and unloading device, carriages movably mounted on said trolley track beam adapted to receive the containers, and a second storage beam also within the container crane structure and being positioned between said trolley track beam and said first storage beam for storing either loaded or unloaded containers handled by said main trolley loading or unloading device. 